This application relates generally to the field of vehicle steering systems and more particularly to automatic steering system during parking.
Hybrid vehicles, typically, utilize two or more energy sources to increase fuel economy. One of the energy sources employed in hybrid vehicles is a high voltage battery which can be charged from the engine using liquid fuel or by capturing regenerative braking energy during driving. Most vehicles employ a power steering system to assist drivers in maneuvering the vehicle at low speeds. The power steering system is usually powered by the engine (during turned ‘ON’ state) and is not operable when the engine is turned off. Electrically powered steering systems, however can be operated even when the engine is turned off, using an electrical energy supply. One such power steering system is the EPAS (Electric Power Assist Steering) installed in certain automobiles (including hybrid vehicles) provided by the Ford Motor Company. Other automobiles may contain similar electric power steering system known to those skilled in the art. The electric power steering system help promote fuel efficiency with an ability to reduce load on the electrical system during no-use times.
The electric power assist steering system may be coupled to a number of assistance modules, providing additional features to a vehicle. One such module is parking assistance that renders capabilities such as auto-parking, parallel parking, and so on to a vehicle, resulting in a convenient or completely automatic parking process. Parking on a slope, however, may require extra vigilance. Typically, while parking on a steep slope a parking brake or a parking pawl is applied to avoid rolling. On a steep slope, however, the parking brake and the parking pawl may sometimes fail, resulting in damages.
Conventionally, as a safety precaution, while parking next to a curb, drivers turn the front wheels toward the road curb when parking on a slope. Whether parked uphill or downhill, turning the front wheels to the curb results in bringing the vehicle to a halt at the curb instead of rolling down the slope, in case the parking brake or pawl fails. This safety precaution, however, is manual, which introduces a number of problems. For example, the driver may simply forget to turn the wheels, or the driver may not be aware of this safety precaution. Moreover, this precaution can only be practiced by a driver who is educated enough to understand the need to turn the front wheels towards the curb.
Additionally, in automobile showrooms, the front wheels of a vehicle are typically turned at an angle for a better aesthetic appeal. Some users may choose to turn their front wheels after parking, for showcase purposes. In such situations, it may be preferred to always park a vehicle with wheels turned. However, presently, a driver has to manually maneuver the steering wheel to turn the front wheels off center.
It would be highly desirable to have an automatic and cost-effective solution for vehicles that ensure wheel positioning after parking.